mounted on a newly installed mounting plate, flush with the top surface of your lower control arms and almost directly above the BJ.

After seeing Bruce's beautiful control arms, it came to me. You don't need to add an upper plate. Just swap left and right arms. This will place the existing plate to the top side and allow you to move the lower shock mount over the BJ Like I was intending.

In regard to lowering the bottom mount, another option is to weld a thick wall tube across the bottom of the control arm, then cut out the middle just wide enough for the damper eye and use a long bolt. Add a .125" plate to each side with a hole drilled to accept the tube OD.

Thanks guys for all the feedback. My goal is to maximize the shock angle (from horizontal) but not to the point that it affects the strength of the LCA or raises the top mount too much. Ideally, I would like the top mount to not be above the top rail but I see no way with these shocks. And, the further you move away from the ball joint, the greater the bending moment. Of course, I can design for that but prefer to minimize the weight of everything. I've got a variety of shock mounts/brackets so I'm trying a few combinations. I really like the ones pictured here where the bracket I have already has a hole in it for the ball joint tab bolt. This arrangement ties in everthing to a central point. The bracket thickness is perfect also as it slides right under the tab. With this configuration, the shock is 54° from horizontal.

So the big question????? How does it take away from the visual look of the car with the upper shock mount higher than the top rail? BTW, I also want to use the upper shock mount as the headlight mount so that may allow me some creative hidding of this fact.

I guess your talking about the view from the front. Some Seven's have round, amber turn signals about 3 inches in OD hanging just below the seven inch headlight, where the headlight center is level with the top of the nose, 4-6 inches forward of the hood edge. The turn signal would be right in front of the upper shock eye.

Shifted gears and started to work on the pedal layout and steering column. First, I needed to locate and mount the seat. I tried using the Miata Seat but I only have 17.5" of width and even with taking apart the hinge system to reduce the seat width, I was still not satisfied so I took the passenger side seat out of my Spec Miata and started designing the mount. I saw a scrape piece of Uni-Strut in the shop and decided to use it as a seat mount as it would allow some adjustment. The race seat is a 20° layback so I had to machine some aluminum blocks to mount the front. The seat fit perfectly and I have about 4" of travel if needed. Losen 4 bolts an the seat slides back and forth. This turned out better than I had thought and was so simple to install. I was a little hesitant using the Uni-Strut but after investigating the strength of it, there is no concern.

The aluminum blocks and channel are strong, but the nutplate washers inside the channel, held only at the edges by the channel are not. Consider what happens when a vehicle is rear ended. A couple hundred pounds of driver pushes aft on the seat and the belts are useless.

The only thing that keeps this seat from sliding along the track is the tightness of the nutplate/washers inside the track at their edges. It looks like they may bend simply from fully tightening the bolts. The washers can bend at the edges and the front of the seat would likely come out of the track, cracking the driver and passengers skulls against the roll bar.

You could beef up the channel internal hardware for more clamping pressure and resistance to pulling out, and add a bolt in the side of the channel to prevent over travel.

Adjustable seat tracks on most bucket seats are very similar to each other and easy to adapt, with teeth that engage on each side to prevent sliding along the track from an impact. On used tracks where the upper mounting flange has odd steps, the flange can be trimmed off and replaced with steel strip. I recall new universal adjustable tracks cost about $20 per seat. I think it was from Speedway Motors. The passenger seat does not need to be adjustable.

Thanks for the feedback. Sliding is a concern but I would not expect the forces during a rear inpact to be parallel to the rails. The CG of the driver creates a moment around the rear connection which makes the front want to lift, not slide during a rear impact. The slide plates used in the unistrut have ridges that grip the lips and I believe you would be hard presses to move these once tightened down. I will also have a rear seat back brace (adjustable as well). If sliding is still a concern for others, a simple solution is to lay a piece of tubing inside the track like you do for the sliding glass doors. However, if you look at the data sheets, using uni-strut to support a 2" pipe with a pipe strap (uses 2-strut nuts - equalivant to one side of the seat), the pullout ultimate load is 5,333 lbs and the slip along is 6,800 lbs. I had considered using universal seat rails but the uni-strut gives the chassis a little extra stiffness and is probably lower than the typical seat rail. Plus, it fit the locost theme.

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